Floating fire-prevention equipment



P w, W51 c. H. MAESHALL 2548,3M

FLOATING FIRE PREVENTION EQUIPMENT Filed Oct. 8, 1945 2 Sheets-Sheet 1 #233 2. INVENTO 4 CHHZLEG H. mam/ 0A4.

' ATTORNEY C. H. MARSHALL v FLOATING FIRE PREVENTION EQUIPMENT A rifi w, 1951 2 Sheets-Sheet 2 Filed Oct. 8, 1945 INVENTOR RC/MRLES H. PQ RS/VQLL.

mm m n his Patented Apr. 10, 1951 FLOATING FIRE-PREVENTION EQUIPMENT Charles H. Marshall, Grafton, Pa., assignor to Koppers Company, Inc., Pittsburgh, Pa., a corporation of Delaware Application October 8, 1945, Serial No. 620,956

Claims. 1

This invention relates to fire extinguishing apparatus. More particularly the invention relates to apparatus for extinguishing fires of an inflammable liquid stored in tanks where the level of the liquid rises and falls as liquid is added to or withdrawn from the tank.

The storage of volatile inflammable liquid, such as benzol, toluol, gasoline and the like, involves a serious hazard from fires because the upper portion of the tank is always filled with a vapor which will burn with explosive violence.

Attempts have been made to mount fire extinguishing apparatus in the top of oil storage tanks, which may be automatic in their operation or may be manually operated for extinguishing fires. Such fire fighting equipment has not been satisfactory because oil tank fires are often accompanied with an explosion which generally destroys the fire fighting equipment. Further, if the fire extinguishing apparatus mounted at or above the oil level in a tank is not destroyed by an explosion it will be put out of operation by, a fire so that it is not effective in extinguishing a fire if the water is not turned on quickly. This has been caused by the piping becoming white hot in a few seconds and when the water was turned on steam was generated so fast that the piping was blown to pieces and th water never reached the spray heads.

The primary object in the present invention is to provide an apparatus which will be effective in extinguishing a fire within a tank containing an inflammable liquid and will not be destroyed or rendered inoperative by a fire or explosion within the tank.

Another object of the invention is to provide an apparatus which will maintainthe fire extinguishing equipment closely adjacent to the surface of the inflammable liquid so as to be most effective in extinguishing a fire.

An important feature of the present invention consists in supporting the fire fighting fluid distributing apparatus closely adjacent to and movable With the surface of the inflammable liquid being stored wherein practically all of the extinguishin apparatus is wholly submerged in the liquid and such portions as are emergent are heat insulated so that it will not be overheated or destroyed by a fire on the surface of the liquid. With this arrangement the fire extinguishing apparatus will properly function in distributing a fire extinguishing fluid over the entire surface of the burning fluid.

Accordingly a further object of the invention is to provide a fire extinguishing apparatus which will deliver a fire fighting fluid closely adjacent to the surface of a burning liquid without being destroyed by the heat of fire.

In the accompanying drawings forming a part of this specification and showing for purposes of exemplification a preferred form of apparatus in which the invention may be embodied and practiced but Without limiting the claimed invention specifically to such illustrative instance or instances:

Figure 1 is a horizontal plan view illustrating diagrammatically a general arrangement of apparatus embodying the present improvement, its relation to the tank, and suggested arrangement of floats and sprays, together with guide means, and flexible supply means for fire fighting fluid, with relation to the spray distribution system and the tank walls; I

Figure2 is a diagrammatic vertical cross-sectional View of the apparatus shown in Figure 1;

Figure 3 is a diagrammatic vertical crosssectional view taken through one of the floats, illustrating the preferred form of connection of the same to the distributing system for the spray heads, to maintain the distributing system submerged and the spray heads emerged, while permitting limited free shifting movement of the float relative to the distribution system:

Figure 4 is a horizontal plan view, partly in cross-section, of a portion of the spray distribution system and one of the floats, illustrating a modified form of construction for connecting the distributing systemwith the floats, to maintain the distribution system submerged, while permitting limited free shifting movement of the float relative to the distribution system, and also illustrating a form of guide means for guiding the floating unit during its rise and descent;

Figure 5 is a view, in end elevation being partly in transverse cross-section, of the float as illus-' trated in Figure 4, illustrating the preferred embodiment of insulating the insulated floats;

Figure 6 is a view, in side elevation being partly in longitudinal cross-section, of the float illustrated in Figure 4, further illustrating the preferred embodiment of insulating the insulated floats;

Figure '7 is a sectional-elevational view illustrating diagrammatically the continuous drain and valve means for automatically closing the same off from the system in response to the pressure of inflowing flre fighting fluent medium passing to the supply means for delivery of the same to the distributing header for distribution to the sprays; and

Figure 8 is a sectional elevational view diagrammatically illustrating the insulated sprays and their pipe connections to their fluid material distribution system, and the preferred mode of construction for insulating the same.

The embodiments of the invention shown on the drawings are particularly designed and adapted for use in connection with oil tanks such as is usually employed for storage of large volumes of oil, and which are susceptible to destruction as a result of sudden, unexpected, and unforeseeable surface fires, often preceded or followed by surface gas explosions.

Referring to the drawings, indicates an oil tank commonly employed for storage of benzol, gasoline, crude oil or other inflammable liquid, which tank has its bottom mounted on a concrete base, II, and is provided with a roof, i2, connecting with the top of the cylindrical wall, 13, of the tank. The tank is provided with the usual means for introducing at 9 and a swing pipe for withdrawal at 9' of oil or other inflammable liquid from an accumulated body i6 thereof within the tank. For fighting sudden and unexpected fires on the surface of the oil or other inflammable liquid by means of sprays of water or other fluid material over the surface l5 of the oil for prevention of ignition of, or quenching, or otherwise extinguishing, a fire on the surface of the oil, there is provided within the tank, in accordance with the present invention, fire fighting equipment consisting of a floating unit comprising spray-means, in the present instance in the form of a series of emergent heat insulated spray heads l4 adapted to project always closely above the top level 5 of body I6 01 oil or other liquids, and to simultaneously spray and cover the entire surface area IE of the oil bath [6 with water or other fire fighting fluid material immediately in emergency to prevent or quench a fire on the surface of the oil. The spray heads M are connected by spaced upwardly extending heat-insulated pipe connections I! with a submergent distributing system of connected piping :8 for distributing simultaneously to each of the spray heads 14, through their pipe connections ll, water or other fluid material from a submerged flexible supply conduit !9 connecting the distributing system of piping IS with a pipe line which is connected with a source of water, of other fluidic material for the purpose, outside the tank l8.

Floats 2!, in the form of tubular buoyant metallic tanks are connected with the system of pipes and sprays so as to freely floatingly suspend the same in a body of inflammable liquid 16 in the tank in such manner that the entire apparatus rises and falls as a unit with changes in elevation of the surface [5 of the body 26 of liquid. The spray heads l4 are connected with the distributing piping l8, and the latter is connected with the floats 2| so that the sprays i4 and at least a portion of their connecting piping I! always are maintained closely above the level of the surface 15 of the body of liquid 56 while the distributing piping i8 is maintained always wholly submerged below such top surface H), as the unit rises and falls with changes in elevation of the top level 15 of the body of inflammable liquid. In the embodiment of the invention shown on the drawings the distributing system 18 is constructed of connected piping in the form of a spider 22 comprising a polygonal manifold perimeter 23 and radial conduits 24 structurall and communicably connected therewith and also structurally as well as communicably intersecting at the center 25 of the floating unit. The floats 2| are arranged in spaced relation to each other and connected with the pipes forming the spider 22 at properly located points, for example as shown, so as to uniformly support the spider 22, which also carries the spray heads 14 and their connecting piping l1 including those with horizontal branch pipe connections 25.

Thus with any rising or lowering of the surface of the body of inflammable liquid in the tank the sprays M are always maintained at approximately the same relative position in respect of the surface 15 of the liquid it in the tank :0. There will, of course, be a slight difference in their elevation relative to the top surface i5 of the liquid [6, depending on whether the system of pipes is empty or full of water or other fluent material, as when the sprays are in operation for spraying such fluent material, and also when the floating unit recedes close to the bottom of the tank, as when the depth of the body it of liquid is relatively shallow as a result of depletion of its volume.

The spider 22 is held concentrically in the tank, as the spider, sprays and floats rise and fall as a unitary whole with changes in elevation of the tank, by co-acting means on the floating unit and the tank, such for example as two or more, in the present instance four, vertical guides in the form of tracks 2! fastened to the inside of the vertical cylindrical side wall 13 of the tank H] for engagement with guide rollers such as the flanged wheels 28 which are fastened to the floating unit so as to ride up and down on the tracks as the floating unit rises or falls.

Figure 4 illustrates one form of construction for this purpose, in which one corner of the spider opposite to one of the vertical guides 21 is employed to carry the flanged wheels 28. In this example the guide wheel 28 is carried by a bracket 29 fastened on one end of a pipe 30 forming an extension of the spider 22 so as to be always submerged below the top level I5 of the body is of inflammable liquid at the same level as that of the submerged level of the distributing piping i8. The guide wheels 28 may, however, be located on a bracket so as to extend always above the surface l5 of the body It of inflammable liquid in much the same manner as the spray heads M.

In the embodiment of the invention shown on the drawing, the spray heads it, are spaced from each other and distributed throughout the floating unit so as to cover the entire horizontal surface area of the top of a body of inflammable liquid in the tank with the fluidic material in the form of a fog, mist, or spray, substantially simultaneously when the sprays M are concurrently fed with water or other fluidic material by the system of distribution piping l8.

To convey water or other fluidic material to the spray heads 14 through spider l8 for the purpose aforesaid, regardless of the elevation of the spider l8 and sprays 14 in the tank, flexible supplypiping I9 is attached to the spider [8 for move ment thereby and communicably connected at one of its ends with the conduit system thereof, preferably at a single zone and at the center 25 where the radial pipes intersect, and is attached at its other end and communicably connected to the fixed or stationary pipe line 2% on the bottom of the tank l0 and leading to and connecting with an inlet for water or other fluent material outside the tank, as at 311'. Any suitable flexible supply-piping [9" can be used. But preferably there is employed as the flexible conduit l9, one that can be folded up and unfolded in sections, progressively, such as a conduit that can be coiled up and uncoiled or preferably one of the general type illustrated diagrammatically in the drawings here, a conduit of the common and well known type exemplified in Figs. 2 and 3 of U. S. Patent 1,136,230 and at 3 in the figure of U. S. Patent 1,177,331, and more especially one of the so-called rotary hose, shown on page 19 of the Chiksan Tool Co.s Catalogue No. 41, which embodies in its construction straight rigid sections 35 connected at their opposite ends by rotary or swing joints 36 so as to fold up and unfold progressively. These swing joints are made to hold tight against leakage for pressure from either inside or outside. They are made regularly for pressures up to 300 lbs. and 3000 lbs. per' sq. 1n.

Figure 1 illustrates diagrammatically the general arrangement of the system, its relation to the tank, a suggested arrangement of floats and sprays, the location of the connection of the flexible conduit with the center of the spider, and the relationship of the vertical guides and rollers or flanged wheels to the spider assembly as a unitary whole. The spray heads l4 may easily be located at any elevation above the surface [5 and turned in any direction. As shown, a float 2| is located closely adjacent and connected to each corner of the polygon, except where the radial pipes 24 extend to and through corners 3! of the polygonal manifold 23 to support the guide rollers for coaction with the guide tracks 21. The floats 2i for the portion of the floating unitary whole as are connected to the radial pipe lines 24 are connected one each closely adjacent the contiguous corner of the polygonal manifold 23, but to the radial pipes 24. However, advantageously two or more of the latter floats are instead connected with their radial pipe lines adjacent the center 25 where more float power is needed due to larger pipe and to compensate for the added weight of the rotary hose or flexible conduit I9. Flotation of the latter may, however, be aided, instead, by supporting part of the weight of the rotary hose I9 by attaching submerged floats to, or closely adjacent to, the swing joints 35, or with larger floats 2| adjacent the polygon corners 31 through which the described radial pipe lines 24 also extend to or through.

In the embodiment of the invention shown on the drawing the spray heads l4 advantageously are in the form of separate and independent spray heads individualized to a specific part of the horizontal area of the tank H! with separate connections i! to the common distributing piping system I8 for concurrently feeding all of the spray heads M in unison from a single central source of supply 19. However, the invention is not limited in all its aspects to such embodiment, but instead the spray means i4 may also comprise common spray-heads such as perforated conduits, but with spaced connections I! individualized to restricted parts thereof, or otherwise allocated to the horizontal area of the tank l0.

In the embodiment of the invention, as illustrated in the drawings, the flexible supply conduit i9 is connected at a single central point 25 with the spider 8 for distributing the water or other fluid material uniformly, at the same pressure, and at the same velocity, simultaneously to all the spray head outlets M for discharge from all of them concurrently in unison so as to reach and cover the entire horizontal area of the uppei surface l5 of the body 16 of inflammable liquid, at one and the same time. To accomplish this the diameter of the distribution piping will decrease from the inlet to the end of the line.

However, such simultaneous supply and concurrent discharge may be otherwise effected from a single source, within the contemplation of the invention by like connection of like flexible conduits l9 to the spider it between the same and the stationary conduit 20, at a plurality of points, rather than at a single region at the center 25 of the tank H], as shown in the embodiment of the invention illustrated on the drawing.

When the tank is empty or nearly empty of oil or other inflammable liquid, it is well to have the spider l8 and floats 21 supported above the bottom I l of the-tank. To this end two or more landing feet 38 are attached to the floats to limit their descent. The feet 38 are secured at opposite sides of the floats, and so as to extend below the floats a distance sufficient to support the floats 2| at a distance sufficiently high above the tank bottom. II that the connections between the floats 2| and the spider [8 will suspend the distributing system 18 and flexible supply conduit IS in a manner preventing-their damage from the weight of the unit as a whole, while yet having the system available for fire prevention even with a very shallow depth-of oil or other inflammable liquid on the tank bottom.

In the operationfof such a system for fighting surface fires on or over a body of inflammable liquid, when such anunexpected' fire suddenly breaks out, with manual and even with automatic operation, there may be some interval of time before the water or other fire fighting fluidic material can be turned on into the system. When the fluidic fire fighting material is introduced over the body of inflammable liquid by supply, distributing and spray equipment supported above the same, as from the tank roof i2 or side wall [3, so as to rise and fall in following the change in elevation of the top level 15 of the body [6 of inflammable liquid, in order to provide a blanket or cover of foam, or spray, or mist of liquid, immediately and closely over the top surface I5 of the burning liquid, it often happens that the fire is preceded by a surface explosion over the oil or inflammable liquid, which blows the roof l2 of the tank off, or otherwise destroys or wrecks the fire flighting equipment. To avoid this the art has developed floating equipment in which a spray head is floatingly supported closely over the surface of the body of liquid and fed by a submerged floating supply connection and together connected with a float on the surface of the liquid, to rise and fall as a unit with the level of the liquid.

Notwithstanding wide development of the art in this direction, it sometimes happens that, when it is needed, a present type of spray equipment will not work. An oil fire gets extremely hot in a hurry. A flre starts and sometimes by the time the water is turned on, especially if it is a manual operation, the piping is red or white hot and the water or other fluidic material never reaches'the sprays. This leaves the system useless and sometimes completely Wrecked.

The trouble is caused by some of the water being flashed into steam when it strikes the hot piping. The steam is formed ahead of the main body of the water and'cannot get through the nozzles as fast as it is generated and, therefore. holds the water back. The piping has been known to blow to pieces without a surface explosion, which the present inventor attributes as due to the fact that pressure generated in the aforesaid manner was suficient to cause the piping to burst or explode.

In accordance with the present invention, the horizontal distributing system of piping l3, when employed, is connected with the floats 2*. so that the water distribution piping l8 for horizontally distributing water simultaneously to the spray heads M from the submerged flexible supply conduit l9, as well as the flexible supply conduit 69 are always maintained wholly submerged at a level suflicient below the top surface 15 of the main body N5 of inflammable liquid that the piping never gets hot enough from the heat of a fire of burning oil or equivalent on the surface of the liquid, to burst or generate internal back pressure or become afiected by a gas explosion over the body of liquid as would obtain were such horizontal distributing system of piping l8 connected with the floats so as to be spaced above, or floated on the surface.

The emergent portions of the sprays l4 and their connections ll with the horizontal distribution piping E8, as well as the emergent portions of the floats 2 i, that are exposed to the to most level of the body of inflammable oil, where the burning of the oil can take place, or to the gas space above the same, are insulated to prevent such exposed portions from being heated by a surface fire to a temperature which would melt, or burn them, or generate internal pressure, resulting in their bursting, or in creation of a back pressure delaying or preventing ready flow of water or other fluid material to and through the sprays and out over the surface of the liquid body id, as and when needed, and

until the water or other fluid material has been turned on into the system, manually or automatically, in emergency in case of an unexpected sudden fire, or explosion, and has opportunity to reach and discharge from the spray heads over the body of liquid i6 and floats 2!, as in a case where it is not possible to turn on the water or other fluid material quickly. It is extremely important, and possibly vital, that the horizontal distributing piping l8 should be and is connected with the floats so as to be always submerged at a level sufliciently low, and that the insulation should be and is sufficient to protect the exposed equipment, from being over-heated and to maintain them relatively cool for at least a little while until the water or other fluid material comes on in a raging fire, or instances where a fire gets extremely hot in a hurry.

Instead of employing insulated exposed sprays, connections and floats for the purpose, they may advantageously be constructed of fire resistant, non-combustible, material of very low heat conductivity. Preferablyythey are formed of metal and insulated as shown in Figs. 5 to 8. Advantageously, as therein shown substantially all portions of the spray heads i4, except the portions containing the spray ports 39, and all of the exposed or emergent portions of the spray pipeconnections H and of the floats 2| are covered with a layer 32 of fire resistant heat-insulating material such as asbestos or the like. Such covering 32 is carried down far enough to insure protecting also those parts in the position closest to'the surface of the liquid being protected. Advantageously only the various exposable portions of the elements are provided with the protective covering 32 of fire resistant heat insulating material, and the lower-portion thereof which might come in contact with the body of inflammable liquid is encased in a liquid-tight metal support 3i welded to the pipe connections H and to the floats 2i to keep the insulation 32 from contact with or absorbing liquid from the body of inflammable liquid 116. The floats 2! may, of course, be other than tubular buoyant tanks, and be constructed of other material than metal, but insulated as above described. Preferably, however, the insulated floats as employed are advantageously of the tubular metallic buoyanttank type, illustrated in Figures 3 to 6.

In operation of the apparatus of the invention as shown on the drawing, in the event of a surface fire, water or other fluid material, when manually or automatically turned on, enters from outside the tank ill through inlet pipe 34, flows upwardly and then horizontally through the fixed supply pipe into the flexible supply conduit l9, whence it flows into the center of the spider l8, entering the radial pipes 24 simultaneously and flowing thence horizontally through said pipes 26 concurrently to all of the branches 2% and to all of the corners of the polygonal manifold, which distribute the water at the same velocity, pressures, and volume to the respective vertical pipe connections ll leading to the spray heads Hi, which latter discharge the same over the respective areas assigned to them, closely over the top surface it of the body of inflammable liquid is such as oil, thus covering the entire area for preventing ignition, quenching, or otherwise retarding, a surface fire, in any elevated position of the top surface 15 and of the floating unit, which follows the same as the level it rises and falls.

In the course of construction or use of the apparatus there might be some leakage of the oil or other inflammable liquid into the submerged horizontally distributing piping system [8, the flexible supply conduit l9, and the fixed conduit 20. Should leakage occur, the spray heads M would spray inflammable liquid into the air or gas space in the tank above the top level I 5 of the liquid 16, for a few seconds after the water or other fluent material is turned on into the system. As a safety precaution, a drain 80, Fig. 7, is connected with the system, below the connection of the water inlet 34.- to the fixed supply conduit as, for continuously draining and disposing to a sump M of any possible liquid leakage from piping which leads to the distributing system. The drain is provided with a valve 32 for closing the same when the water or other fluid material is turned on to fight a fire. Otherwise there would be a loss of pressure, and velocity, and fluid volume to the spray heads. Normally the drain valve 42 is open and drains continuously into the sump or drain pit ii I. Conventional pressure responsive valve actuating means, 43, operable by the pressure of water or other fluid material under pressure, is connected with the fluid pressure line 3 1 and to the drain valve 52 to automatically close the drain valve 52 when the water or other fluid pressure is turned on thus preventing loss of pressure and fluid material. When the water or other fluid pressure is turned off the drain valve 52 is automatically opened again or may be opened by hand,

As illustrated in Figure 2, conventional appa ratus is provided for automatically supplying the fire extinguishing fluid. To accomplish this a valve 59 is mounted in the fluid supply line 35,

which may be any of the well-known weight operated valves. To control the operation of the valve 50, metal bulbs 53 connected in an expansion system are mounted in the upper inner surface of the tank which are connected by piping with the valve weight releasing mechanism. The construction being such that if a flre starts within the tank and the bulbs become heated, the gas within the bulbs expands to release the valve weight 54 to open the valve 50 about pivot 55.

The level of the liquid accumulated in the sump is determinable from outside the same by means of a tell-tale float 45,

To insure the unfolding and folding of the sections 35 of the flexible supply conduit I9, progressively during the rising and lowering of the distributing element 18, the adjacent sections 35- are connected by flexible lifting means, such as a chain 44, or other flexible linkage, to limit the amount of angularity of the movement of the sections 35, such as the legs of the rotary hose one with the other about their rotary joints 36. Such construction prevents binding of the movements of the sections of the flexible conduit when the level of the surface I is lowered as might occur if moved past dead center during their previous elevations, which might result in distortion or tilting culminating in further leakage, and such construction also makes possible and assures that the connection of the flexible conduit to the distributing piping I8 is always in the same position relative to the vertical central axis 25 of the tank, in any of the various elevated positions of the distributing piping system 18 and the sprays l4 and floats 2!, when floated together as a unitary whole.

The floats 2| are connected with the elements forming the floating unitary whole, according to the present improvement, by flexible connections permitting a sympathetic shifting movement of the floats with the movement of the fluid in storage without movement of the rest of the distributing structure. Such flexible or yieldable connection between the floats and the rest of the floating unit is of further advantage in event of an explosion on or over the surface of the liquid body H5, in which event the explosive forces might travel horizontally across the tank and move the floats more or less violently.

Fig. 3, and Figs. 4 to 6, illustrate two modes of construction which are especially practical and feasible for the aforesaid purpose of flexibly or yieldably connecting the floats to the system of pipes. The embodiment shown in Fig. 3 is preferred because of the greater flexibility afforded in the case of surface explosions, and the greater ease and simplicity in construction and installation. In the form of construction illustrated in Fig. 3, the piping I8 is supported from the floats by metal chains d5 secured one at each end of the tubular metallic buoyant tanks 2!, as by means of brackets 41. The chains 46 are secured to the lowermost portions of the tanks, and are of such length that the distributing piping I8 is always maintained wholly submerged at a depth where the piping will not be over-heated by a surface fire, or affected by explosive forces passing over the surface of the liquid. The chains 46 are secured to the piping l8 b means of metal pads 46' welded or otherwise fastened to the piping, and the brackets 41 are likewise welded or otherwise fastened to the metal float-tanks 2|. The horizontal branch conduit connections are also connected with pipes 24 so as to be also maintained wholly submerged at a level sufficiently low below the top surface I5 to avoid their overheating or being affected by surface explosions. Their spray heads I4, however, extend always above the top surface l5.

In the embodiment illustrated in Figs. 4 to 6, the tubular metal buoyant float-tanks 2| are pierced by a liquid-tight conduit 48 extending through the same and open at their opposite ends 49, for insertion of sections of the piping I8. In this embodiment, the floats 2| are flexibly or yieldably connected as aforesaid to the piping l8 by extending one of the pipe members of the spider l8 loosely through the conduits 48, which conduits 48 are located sufficiently below the longitudinal central axis of the respective floats 2! to maintain the piping of the spider l8 always submerged at a level sufflciently below the top surface [5 of the liquid [6, as in the embodiment illustrated in Fig. 3, and as and for the purposes of invention hereinabove set forth and described. In the float-tanks 2| as illustrated in Figs, 3 to 6, the tank ends 5| are also insulted and capped as above described, the metal caps 3| being also welded to the tank-floats to keep the insulation from the liquid below and surrounding the same,-

in the same manner as with the spray heads I4. In the embodiment of the invention as illustrated in Figs. 4 to 6, the float-tanks 2! may be provided with means for preventing the float-tanks from shifting longitudinally therealong, by means of co-acting lugs 52 on the spider 18, the lugs being welded thereto after the float-tanks are in place on the spider.

The invention as hereinabove set forth is embodied in particular forms, but may be variously embodied within the scope of the following claims.

I claim:

1. In combination with an oil tank and a fixed inlet at the lower part of said tank, for inflow of fluid fire-fighting medium under pressure to said tank; of a floating unit comprising sub' merged distributing piping system of communi acting means on said tank and said floating unit for guiding the floating unit during such rise and fall, and flexible connections between the floats and the rest of the unit, for floatingly supporting the unit from the floats with the insulated spray-means and the insulated floats always emergent, and the distributing piping radial and perimetrical conduits always submerged.

2. In combination with a tank for storing inflammable liquid and a fixed inlet at thelower part of said tank, for inflow of fluid fire fighting material to within said tank, of a floating unit comprising a series of emergent spray headsdistributed at spaced intervals across the horizontal area of the tank, a system of submergent distributing piping connected to said spray heads, emergent floats attached to said piping system for buoyantly supporting the unit from the surface of the liquid to be stored in the tank, and a submergent adjustable fluid-conducting piping connection between the fixed inlet pipe and the distributing piping for conducting fluid fire fighting material from the fixed inlet to the spray heads through the submergent distributing piping, said submergent distributing piping, and emergent floats, and spray heads being disposed relative to each other in the unit so that the fluid conducting and the distributing piping will be supported by the floats in a wholly submerged condition below, while the spray heads and floats are emergent a short distance above, the surface of the liquid being stored, and said spray heads and floats having their emergent portions, which extend a short distance above the surface of the liquid, heat insulated by means of an outer covering of fire resistant non-combustible heat insulation material of lower heat conductivity.

3. Apparatus as claimed in claim 2, and in which the adjustable fluid-conducting piping connection comprises an extensible conduit of a series of sections ioldable successively, and in which each foldable section is connected with next one in the series by flexible lifting means which limit the extent of their unfolding in succession to less than a right angle upon their rise with the unit as it floats higher up to difierent elevations.

4. Apparatus as cliamed in claim 3, and in which each foldable section is connected at opposite ends to the end of a next succeeding section by means of a hinged joint.

5. Apparatus as claimed in claim 2, and in which the floats are connected with the submergent distributing piping for some free, but limited'horizontal and upward and downward movement relative thereto, which affords shifting movement of the floats relative to the unit, to enable them to move with the surge of the liquid being stored and under pressure of an explosion above the surface of the liquid, while the distributing piping remains unaffected by such surge.

6. Apparatus as claimed in claim 2, and which includes valved drain means communicating With the piping of the floating unit between the fixed inlet and the submerged adjustable fluid conoperation by the presence or absence of fluid pressure therefrom, and connected with the drain valve, to open the latter to drain when the supply of fluid pressure through fixed supply pipe is cut oil and to close the drain valve when the supply of fluid pressure is turned on for flow to the floating unit.

'7. The combination defined in claim 2 in which the floats are connected to the distributing piping by chains.

8. The combination defined in claim 2 in which the floats are mounted on the distributing piping so as to be relatively movable on the piping.

9. In combination with an oil tank and a fixed inlet at the lower part of said tank, for inflow of fluid fire-fighting medium under pressure to said tank; of a floating unit comprising submerged distributing piping system of communicably inter-connected radial and perimetrioal conduits provided with spaced heat-insulated emergent branch conduits terminating in heatinsulated emergent spray-outlets, an extensible conduit in foldable sections connecting the fixed inlet with the radial conduits of the distributing piping system at the center of the floating unit,

buoyantly supporting the unit as a floating unitary whole, so as to rise and fall with fluctuations in the height of a body of liquid in said tank; and co-acting means on said tank and said floating unit for guiding the floating unit during such rise and fall; flexible connections between the floats and the rest of the unit, for floatingly supporting the unit from th floats with the insulated spray-means and the insulated floats always emergent, and the distributing piping radial and perimetrical conduits always submerged; ,flexible means inter-connecting structurally adjacent ioldable sections of the extensible conduit, to limit the unfolding movement of its respective foldable sections to an angle less than a right angle, and thus insure dieir progressive folding and unfolding; valved drain means communicating with the piping of the floating unit between the extensible conduit and the fixed inlet; and means automatically operable by the pressure of fluid fire-fighting medium inflowing through the fixed inlet, for closing the valve in the valved drain-means.

10. In fire prevention apparatus for oil tanks and the like, a floating unit comprising submergent upper distributing and lower uprising supply piping, and upper emergent sprays and floats structurally connected together to rise and fall as a floating unit in a body of liquid with fluctuations in the height of the same; the sprays and floats being disposed in the floating unit so as to be always closely emergent above the surface of the liquid as the floating unit rises and falls, for spraying fire-prevention fluid medium closely over the surface of the body of liquid, in the event of a surface fire in any of the elevated positions of the floating unit as it rises and falls with changes in the height of the body of liquid; and the distributing piping being con nected in the floating unit in relation to the floats for submergence at a level sufdciently below the surface of the liquid at all times as the floating unit rises and falls With changes of elevation of the body of liquid, and the emergent sprays and floats being insulated with an outer covering of fire resistant non-combustible heat-insulation material of low heat conductivity, to prevent their being overheated by a surface fire and to avoid inte-rial pressure being thereby generated in them, which otherwise could occur and would be destructive of them or prevent flow of fluid medium to the sprays, and until fluid medium can reach and discharge from the sprays in event of a surface fire on the body of liquid; and a liquid tight basal covering for the insulation covering of said sprays and floats to prevent the so-insulated sprays and floats from becoming water-logged.

11. The combination with an oil tank, an inlet pipe for fluid fire-fighting material to said tank, a submergent extensible conduit connected to said inlet pipe and located in said tank, and a float connected to the upper portion of the extensible conduit for rise and fall of the upper portion of the submergent extensible conduit together with the float with fluctuations in the height of a body of liquid in the tank, of a spray communicably connected to the upper portion of the extensible conduit to discharge fluid material therefrom and structurall connected as a unit with the float and extensible conduit to rise and fall as a unit therewith, said spray being located in the unit so as to always be emergent closely above the top surface of the body of liquid as the unit rises and falls with fluctuations in the height of the liquid, and the spray and the emergent portions of its connection with the rest of the unit being heat-insulated with an outer covering of fire resistant non-combustible heatinsulation material of low heat conductivity, to prevent their being overheated by a fire on or over the surface and to avoid internal pressure being thereby generated therein, which would be destructive of them or prevent flow of fluid medium to the sprays, until fluid fire fighting material can be turned on into the inlet pipe and reach and discharge from the spray in event of outbreak of a fire on the surface of the body of liquid.

12. The combination with an oil tank, an inlet pipe for fluid fire-fighting material to said tank, a submergent extensible conduit connected to said inlet pipe and located in said tank, and an emergent spray connected to the extensible conduit to discharge fluid material therefrom into said tank over the surface of a body of liquid in the tank, of an emergent float connected as a unit with the spray and the upper portion of the extensible conduit so as to rise and fall therewith as a floating unit with fluctuations in the height of the body of liquid in the tank, said spray and float bein disposed in the unit so as to be emergent above the surface of the body of liquid when the unit floats therein, and said emergent float having its emergent portions heat-insulated with an outer covering of fire resistant, noncombustible heat-insulation material, to prevent the emergent portions of the float from being overheated by a fire on 01' over the surface'and to avoid internal pressure being thereb generated in the float, which would be destructive of its floating capacity, until fluid fire fighting material can be turned on into the inlet pipe and reach and discharge from the spray in event of outbreak of a fire on or over the surface of the body of liquid.

13. The combination with an oil storage tank and a fixed inlet for supply of fluid fire fighting material into said tank, submergent conduit means within said tank for leading in of fluid material from said fixed inlet, discharge means associated with said submergent conduit means for delivery of the fluid material therefrom into fire-fighting relation with fire within said tank, of floats mounted on said submergent conduit means so as to be relativel movable thereon, for raising and lowering said submergent conduit means and said discharge means as the surface of a body of liquid being stored in said tank rises and falls due to the changes in the level of the liquid being stored in the tank.

14. The combination with an oil storage tank material therefrom into fire-fighting relation with fire within said tank, of valved drain means communicating with the submergent conduit means between the same and the fixed inlet for drainage of fluid from the discharge means and the submergent conduit means, fluid pressure operated valve means in communication with the fixed inlet pipe for closing operation of the drain valve by thefiuid pressure, and opening operation of said drain valve in the absence of fluid pressure, passing from the fixed inlet to the submergent conduit means, to open the drain valve when the supply of fluid pressure is cut off and to close the drain valve when the supply of fluid pressure is turned on for flow to the submergent conduit means.

15. An oil tank float provided with a flexible conduit leading downwardly from the same and adapted to fold and unfold as the float-falls and rises due to changes in the level of the liquid on which the float floats, said conduit comprising a series of sections each of which is connected at its opposite ends by a hinged joint to the ends of each of the next succeeding sections, and means connecting each section with the next section for limiting the extent of their unfolding to an acute angle as they unfold successively upon their rise with the float as it floats higher up to different elevations with rise in elevation of the top level of the liquid on which the float floats.

CHARLES H. MARSHALL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 170,060 Connelly Nov. 16, 1875 239,217 Bishop Mar. 22, 1881 984,994 Armstrong Feb. 21, 1911 1,136,230 Holmes Apr. 20, 1915 1,177,331 Holmes Mar. 28, 1916 1,356,207 Holmes Oct. 19, 1920 1,714,015 Gallagher May 21, 1929 1,843,882 Norling Feb. 2, 1932 FOREIGN PATENTS Number Country Date 735,644 France Nov. 12, 1932 

